1. Field of the Invention
The invention relates to a resist pattern-forming method.
2. Discussion of the Background
A reduction in the line width of a resist pattern used for lithography has been desired along with miniaturization of the structure of electronic devices (e.g., semiconductor devices and liquid crystal devices). A fine resist pattern having a line width of about 90 nm can be formed using short-wavelength radiation (e.g., ArF excimer laser light) and a radiation-sensitive resin composition that responds to such short-wavelength radiation. However, it will be required to form a finer resist pattern in the future.
As technology that makes it possible to form a finer pattern by utilizing the characteristics of the radiation-sensitive resin composition, technology that utilizes an organic solvent having a polarity lower than that of an alkaline aqueous solution as the developer has been proposed (see Japanese Patent Application Publication (KOKAI) No. 2000-199953). This technology makes it possible to increase the optical contrast, so that a finer pattern can be formed.
However, it will be required to form a resist pattern in a finer area in the future. A resist pattern-forming method that can deal with various resist patterns such as a trench pattern (e.g., line-and-space pattern) and a hole pattern (e.g., contact hole pattern), and can form a resist pattern that exhibits an excellent depth of focus and an excellent pattern shape, and also exhibits excellent critical dimension uniformity (CDU) (when forming a hole pattern) or excellent pattern collapse resistance (when forming a trench pattern), has been desired.